Inoculation with phosphate-solubilizing bacteria (PSB) and the application of phosphorus (P) sources can improve soil P availability, enhancing the sustainability and efficiency of agricultural systems. The implementation of this technology in perennial grasses, such as Kikuyu grass, for cattle feed in soils with high P retention, such as Andisols, has been little explored. The objective of this study was to evaluate the productive response of Kikuyu grass and soil P dynamics to BSF inoculation with different P sources. The experiment was conducted on a Kikuyu pasture, which was evaluated for 18 months (September 2020 to March 2022). Three P fertilizers with different solubility levels were applied: diammonium phosphate (DAP) (high-solubility), rock phosphate (RP), and compost (OM) (low-solubility). Moreover, the inoculation of a PSB consortium (Azospirillum brasilense D7, Rhizobium leguminosarum T88 and Herbaspirillum sp. AP21) was tested. Inoculation with PSB and fertilization with rock phosphate (RP) increased soil labile P and acid phosphomonoesterase activity. Increased grass yield and quality were related with higher soil inorganic P (Pi) availability. This study validated, under field conditions, the benefits of PSB inoculation for soil P availability and Kikuyu grass productivity.

Intensive land-use change, the overgrazing of pastures, and the poor soil management in the Amazon region induce significant soil chemical degradation, causing alterations in the soil phosphorus (P) dynamics. Here, we studied the changes in P fractions and availability throughout the soil profile along a chronosequence composed of four study areas representing the typical land-use transition from forest to pasture for extensive cattle ranching in the Colombian Amazon region: (i) Forest—Deforested—Pasture 4 years old and Pasture established >25 years after deforestation. Soil samples collected at 0–10, 10–20, 20–30, and 30–40 cm depth were used for the sequential fractionation of P, determination of acid phosphatase activity and soil organic carbon (C) content, and calculation of C:organic P (Po) ratio and P stocks. Our results showed that the land-use change caused a decrease of 31.1% in the fractions of labile inorganic P, with the mineralization of organic P by phosphatase enzyme playing an essential role in the P availability. Although according to the C:Po ratio of the deeper layer the P seems to be sufficient to satisfy the plant needs of all the land uses assessed, the exploitation of soil nutrients in pastures reduced by 6.1% the moderately and non-labile P stock. Given the role of cattle ranching in the economy of tropical countries, it is imperative to adopt strategies of soil P management to improve P-use efficiency, avoiding the degradation of grazing land resources while ensuring the long-term sustainability of rangeland livestock and decrease further deforestation of the Amazon rainforest.

A Revista Ciência Agronômica é voltada para estudos relacionados com as Ciências Rurais e Recursos Naturais

Microbial communities regulate the transformation and stabilization of nutrients during composting; however, current knowledge on their specific functional roles across composting stages remains poorly integrated. This review examines the pivotal role of microbial mediation in nitrogen (N) and phosphorus (P) dynamics during composting and their subsequent impact on soil health. We analyze how biotechnological interventions—specifically the inoculation of functional microbial consortia (phosphate-solubilizing bacteria, phosphate-accumulating bacteria, and nitrifiers) and the application of physicochemical additives such as biochar—reconfigure microbial succession patterns to mitigate gaseous losses and enhance nutrient bioavailability. Several studies have reported substantial reductions in ammonia (NH₃) and nitrous oxide (N₂O) emissions under specific composting conditions, while simultaneously promoting the stabilization of labile P into more recalcitrant forms, including polyphosphates. Furthermore, the application of mature compost to agricultural systems induces a profound ecological reassembly of the soil microbiome, shifting community composition toward copiotrophic dominance (Pseudomonadota and Bacteroidota) and increasing functional redundancy. These microbial and functional shifts enhance soil resilience to environmental stressors—such as drought and temperature fluctuations—by stabilizing extracellular enzyme activity and reinforcing microbial co-occurrence networks. We conclude that managing microbial interactions along the compost–soil continuum is essential for developing organic amendments optimized for specific soil and crop requirements. This integrated approach represents a cornerstone of precision sustainable agriculture and contributes to climate change mitigation through soil health restoration.